Lightning Protection - Out with the old, in with the new

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The introduction of BS EN 62305: Protection Against Lightning on 1 September 2008 is already having a profound impact on the industry and its customers says Colin McElhone, managing director at Omega Red Group

Having spent the past two years preparing for the introduction of the new standard, it shouldn't really be a surprise now it's here.

But like many in the lightning protection industry I have spent my entire working life working under its predecessor and knew it inside out. Doubtless we had all become comfortable with the old standard.

Early indications are that the new standard is already transforming the activities that have governed lightning protection for decades in this country particularly on major developments where there is greater awareness amongst specifiers, architects and building contractors about the need to adhere to its provisions, not least for insurance purposes. Insurers will start to make either new build or renewals subject to the new standard. Failure to comply or at least to show evidence that due process has been followed may well transgress the terms and conditions of the insurance and invalidate it. If a lightning strike was to cause serious disruption to a building or to the IT systems that are so much a part of modern business life but the insurance was invalidated then it could turn out to be a very costly oversight.

Given that the new standard was running in parallel with the old standard for two years then ignorance is no excuse. Developers still drafting tenders to meet the provisions of the old standard will find their plans superseded before they have laid the first brick. If that means going through the whole process again then it could add significantly to overall costs. The new lightning protection standard specifies that Type1 equipotential bonding lightning current arrestor surge protection devices (SPDs) should be installed at the point where services enter the structure, as a minimum, in order to equipotentialise the live cores in the event of a strike. This requirement also applying to any exposed plant, lights, CCTV and sensors that may have cables entering a structure.

More important than the risk of systems failure, is the risk to life. Previously, it was often the case that the lightning protection system was treated as something of an afterthought. The new standard requires precise assessments, designs and costs which means that lightning protection experts now need to be consulted much earlier than was previously the case. An example being the use of reinforcing as a down conductor; if the construction starts with out the required welded or clamped connections at each lift in the columns then they may not be suitable for use in the system and the expense of surface conductors will need to be accepted.

The requirements of the new standard are much more comprehensive and progressive than before and a key requirement is that lightning protection is fully integrated at the design stage of a new development if full use of the savings in using any structural elements can be considered. That means a much greater degree of co-ordination with building services contractors on the project. By integrating the lightning protection at the design stage the developer both meets one of the requirements of the new standard and avoids the need for an expensive retrofit.

The new risk assessment is very technical and comprehensive, but with the right software it has been made easier to calculate the precise risk of a lightning strike to each individual building.  By following the new procedure our engineers have a solid guideline, which highlights the precise requirements for each job. The previous calculation failed technical to illustrate the exact need for lightning protection to the customer; this resulted in some buildings going without.

Depending on the requirements of a particular project there are four separate risks that should be addressed:
1. R1 - Risk of loss of human life
2. R2 - Risk of loss of service to the public
3. R3 - Risk of loss of cultural heritage
4. R4 - Risk of loss of economic value.
The scale of the task is illustrated by the fact that while R1 is addressed under the existing standard, R2 is only partially addressed and then only in an informative appendix. R3 and R4 are included for the first time within the new Standard - completely new requirements with which neither developers nor lightning protection companies have previously had to consider.

While the new standard has many merits, it is long and complex and requires a complete rethink by developers and lightning protection companies because of its effect at every stage - from the initial site survey/tender documentation through design to implementation and ongoing maintenance.

One example of the impact of the new risk assessments is illustrated by work that Omega has done over the years on the lightning protection system at St Paul's Cathedral. The risk of loss of cultural heritage (R3) is entirely new and did not have to be considered within the old standard. In fact, Omega has always taken great care to ensure that no damage was caused to paintings, statues or any of the other artistic treasures in the Cathedral but that was part of Omega's own customer care programme, not a formal requirement. Under the new standard there is an obligation to consider ‘cultural heritage' just as we have always considered the risks to human life and to the structure of a building.

Many organisations are already struggling to cope, finding the new standard too complicated, too time consuming and, yes, too expensive in terms of retraining and reorganisation. Experience counts for a lot in lightning protection but this is a fundamental change that challenges everybody involved to raise their game.

There is, in addition, a legal obligation to test the system every year and the discovery of a necessary and expensive retrofit is unlikely to be welcomed. That is why clients need to be absolutely sure that they choose a specialist lightning protection contractor who can demonstrate a comprehensive knowledge of the new standard and one that has a proven track record.

At Omega Red we have put not only our existing engineers through a rigorous retraining programme regarding the new standard but our sales team and customer care department. That includes every single one of our apprentices at the CITB training centre at Bircham Newton, to which we routinely send more than half of the industry's entire intake. It is very much in the interests of both the lightning protection industry and our colleagues in construction to get up to speed with the new standard as soon as possible if we are all to avoid costly mistakes.

Developers need to put out tenders that challenge a contractor to demonstrate a clear understanding, comprehensive methodology and a proven track record, but must also accept that they will need to have a lot more input in to the design of systems. They will find that the more progressive organisations have been using the 2-year crossover period to refine their understanding and test their processes. Those individuals or organisations that haven't taken the time to open their textbooks, perhaps for the first time in years, will soon start to find themselves out in the cold as BS 6651 no longer exists.

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